Improved machine for milling knife-edges cf scale-beams



tlttrd (staten @tutti @Mira HENRYv FAIRBANKS.- or sT. JOHNSBRY, VERMONT.-

Letters Patent N 98,363, elated December :28, 1869.

The' Schedule referred to in these Letters Patent and making part of the same.

To all whom it may concern:

for milling the knife-edgeswith rounded, instead of plane or hollowed sides, as heretofore I will lirst proceed to describe what I4 consider the best means of carrying out my invention, and'willafterward designate the points which I believe to be new therein. f

The accompanningdrawings form apart of this specification Figure 1 is a' front elevation.-A

Figure;2 is a cross-section, on a larger scale.

Figure 3 shows the relations of certain-parts before commencing to act on apair of knife-edges:

Figure 4 shows the same ou a magnified scale.

Similar letters of reference indicate like parts in all the figures.

I provide a substantial'fxed frame-workof caste iron, and mount two housings so that they carry the milling-tools in line with each other, and at adjustable distances apart, the proper, powerful, and rapid rotary motion being communicated to each by` belts from shafts above.

A-A are the milling-tools. The ,shafts a a, on which they are carried,` are mounted on'stands, .which are separately adjustableon ways lon the fixed flaming. l

The levers to'be treated are mounted successively upon a tilting table, B, and are held, with .their knifeedges accurately in position by resting in gauge-notches in blocks'b. The strain on the knife-edge resting in the notch is partially relieved by means of the wedges or other supports, notrepresented, under the levers. This portion of the apparatus', as also suitable -supports and clampsfat other points, to hold the lever firmly in position on'the tilting table B, maybe rhodi-l tied at will, to adapt themachine to treat dierent levers, and will oder no diflculty to mechanicsaccustomed .to this kind of'ivork. Their function is to hold't-he lever very solidly in place upo'n the tilting table B. Y

On the under side of Athe tilting table, are four halfcylindrical cavities to form bear-ings. The bearings c c are in line with each other, and the bearings c Ac' are also s imilarlyin line. The lines c c and c c are parallel to each other, and at a considerable distance apart..` The table B tilts sometimes upon one set of hearings, c c, and sometimes upon the other set, c c. G is a cross-slide, supported upon cross-ways d, on a. massive centre-piece, D, which latter is fixed upon.

'and forms,-in effect, a portion' of the lixed frame-work of the machine. The cross-slide O carries cylindrical bearings, which are adapted 'to match in the bearings c c and c c'. When either side of the table B is raised,-

the table B and its attached lever are supported on vthe opposite set of bearings, and all the parts thereof describe curves, of which the axis ofthe opposite set of bearingsforms the centre'.

This motion is illustrated in ng. 3, in which the front edge of 'the tilting-'table B is represented as elevated,

and the front bearings c care out of use. As the front' edge is raised or lowered, the entire tilting table- -B, and any lever clamped thereon,` describe a curve around the axis ofthe bearings c' c'. When the front is-lowered until hl front bearings c c come into use,

when the rear'edge 'of vthe tlting'table-'is elevated, 'allthe parts of the table B, and of any lever clamped thereon, describe curves, not around the axis c c', as before, but aroundthe different-and parallel axis c c. In practice, uI so `conduct the operation that the lever is tilted on one axis, c c', to mill one side of any given knife-edge, `and on the other axis, c c, to millthe other side. The motion thus induced, leaves the knife-edge with the sides slightly Ifull or circular, as indicated .in

DI move the tilting table B and the lever mounted thereon, forward and backward, by means of the screw E and hand-Wheel or crankE'. This moves thecrossslide O forwardand backward on the transverse ways,

and-'correspondingly moves forward or backward the tilting table B, and any lever mounted thereon, so as toA bring the knife-edgesinto the proper desired relations to-the milling-tools.

Itis-common totreat the knife-edges on a great nurn'be` -of similar levers in succession ;that is to say,

before commencing to treat the levers of a certain size or style of scale, we prepare a whole lot of levers, say .one hundred or a thousand, and then commence to treat them in succession'.

As the levers are necessarily to be finished all exactly alike, the cross-slide O is required to move backward and forward to exactly thc same extentat each movement.A I prov-ide adjusting-screws e e, tapped through the centre-piece l) at the front, and corresponding screws e e'at the back, to aid each movement. After rightly adjusting these screws e e', lI move the cross-slide C and its connections, bodily forward or backward, until they strike the front adjustiugscrews e e, or the back adjusting-screws e e', as the-case may be.A

I will now describe my means for slowly and strongly tilting the table B and the lever carried thereon.

H is a cross-shaft, mounted in bearings in the fixed frame-work, and turned by a hand-crank, H'. v

It carries -two pinions, h and h, the former at the front and the latter at'tbe back of said machine.

The1 front pinion it, gears in a rack, g, which is 'upon guided by a projecting ridge or way on the iront of the frame, and carries a wedge or long incline, G, which extends about half of its length, as shown inl strong lines in iig. 1. i The back pinionV h', gears into acorresponding rack, y', which, in its turn,carries acorresponding incline, G'. The back incline G', is inclined in the opposite direction, and is fixed on'theopposlteeud of its rack. As the shaft H is turned in one direction or the other, the racks g and y are movedsimultaneously to the left or the right, and the inclines G and G come successively into play, to elevate the corresponding end of the tilting table B.

The elevating-motion is received by small rollers,

or,if preferred, plain pins,vand communicated'throughvertical slides F F'. The front slide It is mounted inv front of the rackg, and the rear slide F is mounted in the rear of the rear rack g'. l

When thc racks are moved to the right, the incline G acts under the pinj, which may have a small roller Y it if preferred, and lifts the'slide I", and causes it telitt the front edge ofthe tilting table B. I clamp on a fresh lever while 'the4 tilting table is inclined to its greatest extent. Assuming, vfor example, that 'the front edge is thus raised and the transverse slide 0 moved back until it strikes the rear adjustingscrews e e', I clamp on a new lever, and commence to turn the crank H' slowly and steadily, so as t'o move the racks g g to the left. This motion lowers the knifeedgesslowly across the line of action of the millingtools, in a curve, of which the axis of the bearings c',

is thecentre.

,After the milling-tool has thus completely milled,

one side of each knife-edge, the motion of the racks gy to the left still v'gradually progressing by the coutinuous and steady turning of the hand-crank H', ,the

iront edge of the. table B continues to descend. After -uow give a few turns to the crank E', so as to move the whole table and its connections bodily forward, by

traversing the transverse slide Cforward until it strikes` the front screws e e ;and now, by continuing the slow `rotation of the hand-crank Hf, I gradually -raise the rear edge of the table B, traversing the knife-edges in contact with the cutting-teeth ofthe milling-tools, until therear faces are nicely milled. This finishing of each rear facewill be on a curve, of which the 'axis c c is the centre. After this cutting is finished, the parts are restored 4to their original position by rapid reverse movements, and the lever is removed, and a fresh one applied. i

It will bereadily seen that by adjusting the front screws e e, and the-back screws e e', so as to allow a greater motion of the transverse slide C,` and its connections, I can move the latter so as to treatdilerent knife-edges at a considrable distance apart. 1t will also be seen that these adjustingscrews are `capable of being set with great delicacy, so that I can, by their means, determine the paths in which the knife-edges traverse along the cutting-edges of' the milling-tools, so as t-o move, more or less, and to raise or -lower the finally-finished edges of the knife-edges.

i By setting the levers at different heights, by means of the wedges N N, or equivalent supports for the levers, and changing the positions of the Vfront and back adjusting-screws, and adjusting all the parts of the machine to correspond, aswill be readily understood by a good workman, I eau not only change, the elevation of the finished edges, but also the angle, and various other conditions of the entire lever, as may be required with each. variety of lever.

as required.

secured by nuts tapped thereon, or by other-anal In practice, Ifork, or divide my vertical slides F F', so that the screw-shaft E may extend across through the centre of each. This, and a great many other details ofthe machine, maybe varied without sacrifi-` cingor seriously affecting 'any of the advantages of the invention.

I propose to adjust the milling-tools independently, outwardand inward, by means ofthe screws L, as represented. I can provide means, also, for adjusting the table 'B and its connections, at various heights, and

lcan use any improved means of holding the levers thereon. I can hold the tilting table B and its connections down, with great firmness, upon its tilting bearings, by means of one or more weights or strong springs, attached either to the middle or to both ends, or other convenient points. "Myimproved machine is susceptible of all the i improved meansof adjusting the milling-tools, and all the other parts which are described Ain my previous patents, or which vare known or used in the arts..4 ,I will not occupy space by describing,in detail, such obvious modifications. I 4

I support'the knife-edges directly, while being cut. I do this by means of two pieces, I I, eac'n 'formed as represented, by having a concavity in its top, adapted to match the rounded back of the knife-edge, and the material of the pieces lis cut away on each side, so 'as to afford a clear path for the teeth of the mills, uu-L der all circumstances.4

'Ihewedges-N may be adjusted inwardor outward with greatuicety, so as to raise or lower the pieces I, The 4lower ends kof the pieces I maybe gous means, so as to hold the whole very firmly, when rightly adjusted. v

- Some of the advantages due to certain `features of my invention may be separately enumerated as follows:

`First, by reason ofthe factthat my table, B, on which `the levers are clamped, is rocked4 ou two diffen ent axes, c 'c andl c' c'; I cut `or mill the two faces of each knife-edge with a slight fulness or rounding, which contributes very greatly to the strength of the knifeedge, without interfering with-its action in other respects.

Second, by reason of thefact that the traverse motion ofthe piece C is controlled by the set-screws e e` de', as specified, I am able to move the work forward and backward rapidly, and to determine the proper distance to which it shallbe moved, with absolute certainty, andto an easily and delicately-adjustable extent. I am also able `to thus determine the elevation of the finished edges above the plate B, and to .govern the range as well as the distanceof the knife-edges` with absolute uniformity, and witha necessity for very little labor or skill. V

Third, by reasonof the employment of my crossshaft H, pnions hlt', racks gg', and inclins G G', thc latter being arranged s o as tov incline in opposite directions, and to act' on the vertical slides 4FF', andV tilting table B, as represented, I am able to give the proper tilting-motion with the force and moderation required, and to vary the motion to any extent required in practice, with very simple and reliable mech anlsm. 'Y

Fourth, by reason cal slides F F' operating as represented, relatively to thetransverse shaft H, the iuclines GG', and crossslideO, I am able to communicate' the proper tiltingmotion in anypositon of the cross-slide, and toin duce the two motions, the tilting and transverse sliding, almost independently of, and unaffected by'each other.

' Filth, by reason of the fact that my support-s, I, are adapted to match the 'under side of the kniieedges, and to. apply thereto directly, actuated by the wedges of the employment of the vcrtii N, as represented, I am able to oier a firm support immediately adjacent to the milling-tools, and without interfering with their action. -There -is less tremble and spring in the work wheny the knife-edges are thus directly supported, than when, as usual, the knifeedges are supported indirectly through the medium' of Wedges, cr other appliances, under the main body ofthe lever.

I claim- 1. In a knife-edg'e-milling machine, substantially as hereinspecified, the rocking table B, tilt-ingr upon two ixel, substantially as and for the purposes herein set ort A 2. In combination with milling-tools A A, and va. tilting table, B,`.carried ona transverse slide, O, the employment of one or more adjusting-screws, e e', arranged and adapted to serye, relatively to the other parts, substantially in the manner and for the purposes herein set forth. 4

3, The within-described combination and arrangement of the tilting'table'B,cross-shaft H, and inclines G G,with their connections, adapted to operate. to-

gether, as and for the purposesherein set forth.

:4. In combination, the -vertical slides F F', the reversed inclines G G', and Across-shaft H, arranged to transmit the proper tilting-motion to the' tilting table B, Without interfering with its transverse motion, sub-4 'stantially as ,and for the purposes herein set forth.

5. In 'a knife-edge-milling machine, thecombination of a Vc:ir ryingc'ahle, B, adapted to feed the work to the milling-tools, the,supporting-pieces I, and adjustingmeans' N, adapted to apply directly under the knife.-

edges, all substantially as and for the purposes herein y 

